Abstract

We have studied the transport and recombination properties of heterostructures by two transient techniques; Time-resolved photoluminescence and resonant coupled photoconductive decay. When the is ordered, the two techniques produce radically different excess-carrier decay characteristics. These data can be explained by invoking a charge-separation mechanism at a type-II heterointerface. At higher excess-carrier injection levels, the charge-separation mechanism vanishes, and the type-I interface properties develop. These data are compatible with the polarization field model of ordered .